Spectrum scrubber

ABSTRACT

A method of enhancing wireless communication performance includes receiving information indicative of a local interferer where the local interferer is identified based on dynamic position information indicative of a position of at least one mobile communication node, performing noise cancellation relative to a received signal by removing an interference signal associated with the local interferer to generate a scrubbed signal, and providing the scrubbed signal for additional signal processing.

TECHNICAL FIELD

Example embodiments generally relate to wireless communications and,more particularly, relate to the use of noise cancellation techniques toenhance communication in potentially noisy environments.

BACKGROUND

High speed data communications and the devices that enable suchcommunications have become ubiquitous in modern society. These devicesmake many users capable of maintaining nearly continuous connectivity tothe Internet and other communication networks. Although these high speeddata connections are available through telephone lines, cable modems orother such devices that have a physical wired connection, wirelessconnections have revolutionized our ability to stay connected withoutsacrificing mobility.

The ubiquity of these wireless communication devices, and the abilitythey provide to stay connected while mobile, has made the acquisition ofsufficient radio frequency (RF) spectrum to support such communicationsof primary importance to those attempting to provide communicationservices to users. Network operators can pay billions of dollars forspectrum in an effort to enhance their ability to serve an everexpanding customer base. Whether or not spectrum is obtained throughpurchase, the clear incentive to network operators is to maximize theirusage of the spectrum that is available to them. As the number of usersemploying a given segment of RF spectrum increases, the possibility ofencountering complications from interference may also increase.Accordingly, it may be desirable to enhance the ability of RF spectrum,including particularly noisy spectrum, to be effectively utilized.

BRIEF SUMMARY OF SOME EXAMPLES

In one example embodiment, a method of enhancing wireless communicationperformance is provided. The method may include receiving informationindicative of a local interferer where the local interferer isidentified based on dynamic position information indicative of aposition of at least one mobile communication node, performing noisecancellation relative to a received signal by removing an interferencesignal associated with the local interferer to generate a scrubbedsignal, and providing the scrubbed signal for additional signalprocessing.

In another example embodiment, an apparatus for enhancing wirelesscommunication performance is provided. The apparatus may includeprocessing circuitry configured for receiving information indicative ofa local interferer where the local interferer is identified based ondynamic position information indicative of a position of at least onemobile communication node, performing noise cancellation relative to areceived signal by removing an interference signal associated with thelocal interferer to generate a scrubbed signal, and providing thescrubbed signal for additional signal processing.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

Having thus described the invention in general terms, reference will nowbe made to the accompanying drawings, which are not necessarily drawn toscale, and wherein:

FIG. 1 illustrates an aircraft moving through the coverage areas ofdifferent access points over time in accordance with an exampleembodiment;

FIG. 2 illustrates a block diagram of a system for employing positionalinformation for assisting with interference mitigation in accordancewith an example embodiment;

FIG. 3 illustrates a block diagram of a network controller that may beemployed to assist performing operations according to an exampleembodiment;

FIG. 4 illustrates a block diagram of a spectrum scrubber in accordancewith an example embodiment; and

FIG. 5 illustrates a block diagram of a method for employing positionalinformation for assisting with interference mitigation in accordancewith an example embodiment.

DETAILED DESCRIPTION

Some example embodiments now will be described more fully hereinafterwith reference to the accompanying drawings, in which some, but not allexample embodiments are shown. Indeed, the examples described andpictured herein should not be construed as being limiting as to thescope, applicability or configuration of the present disclosure. Rather,these example embodiments are provided so that this disclosure willsatisfy applicable legal requirements. Like reference numerals refer tolike elements throughout. Furthermore, as used herein, the term “or” isto be interpreted as a logical operator that results in true wheneverone or more of its operands are true. As used herein, the terms “data,”“content,” “information” and similar terms may be used interchangeablyto refer to data capable of being transmitted, received and/or stored inaccordance with example embodiments. Thus, use of any such terms shouldnot be taken to limit the spirit and scope of example embodiments.

As used in herein, the terms “component,” “module,” and the like areintended to include a computer-related entity, such as but not limitedto hardware, firmware, or a combination of hardware and software. Forexample, a component may be, but is not limited to being, a processrunning on a processor, a processor, an object, an executable, a threadof execution, and/or a computer. By way of example, both an applicationrunning on a computing device and/or the computing device can be acomponent. One or more components can reside within a process and/orthread of execution and a component may be localized on one computerand/or distributed between two or more computers. In addition, thesecomponents can execute from various computer readable media havingvarious data structures stored thereon. The components may communicateby way of local and/or remote processes such as in accordance with asignal having one or more data packets, such as data from one componentinteracting with another component in a local system, distributedsystem, and/or across a network such as the Internet with other systemsby way of the signal.

Artificial intelligence based systems (e.g., explicitly and/orimplicitly trained classifiers) can be employed in connection withperforming inference and/or probabilistic determinations and/orstatistical-based determinations in accordance with one or more aspectsof the subject matter as described hereinafter. As used herein, the term“inference” refers generally to the process of reasoning about orinferring states of the system, environment, and/or user from a set ofobservations as captured via events and/or data. Inference can beemployed to identify a specific context or action, or can generate aprobability distribution over states, for example. The inference can beprobabilistic—that is, the computation of a probability distributionover states of interest based on a consideration of data and events.Inference can also refer to techniques employed for generatinghigher-level events from a set of events and/or data. Such inferenceresults in the construction of new events or actions from a set ofobserved events or stored event data, regardless of whether the eventsare correlated in close temporal proximity, and whether the events anddata come from one or several event and data sources. Variousclassification schemes and/or systems (e.g., support vector machines,neural networks, expert systems, Bayesian belief networks, fuzzy logic,data fusion engines, etc.), for example, can be employed in connectionwith performing automatic and/or inferred actions in connection with thesubject matter.

Thus, for example, some embodiments may provide a network device orsystem in which a component is provided to use local interferenceinformation to support noise cancellation. As such, in some cases,internally or externally derived position information associated with amobile communication node within a network (i.e., a vehicle or aircraftor the communication devices thereon, or other mobile communicationnodes (e.g., satellites)) may be used to consult a library of knowninterferers to obtain an interference profile for the position of themobile communication node. The mobile communication node may thenactively undertake to perform noise cancellation relative to the knowninterferers at or near the position.

Moreover, in some cases, the component may be configured to makeinferences and/or probabilistic determinations about where and when suchnodes will be disadvantageously impacted by various ones of the noisesources (i.e., known interferers), in order to selectively apply noisecancellation techniques when appropriate based on the interferenceprofile for the position. Control signals and functionalities maytherefore be generated for control of base stations and/or mobilecommunication nodes in light of efforts to minimize interference.

FIG. 1 illustrates an example layout of a wireless network 100 includingmultiple cells 102 for providing wireless communication services. Thecells 102 can be implemented by one or more access points 104 tofacilitate supporting wireless communications within a geographicalcoverage area of a given cell 102. In this regard, the one or moreaccess points 104 can communicate with one or more wirelesscommunication devices (not shown) present within a respective cell 102.The access points 104 can be assets of one or more existing wirelessnetworks, and/or carriers supporting such networks. Each access point104 has a wired (or wireless) backhaul connection to the one or moreexisting wireless networks to allow access thereto for the wirelesscommunications devices connected with the access point 104. Moreover,the access points 104 can be provided via cellular towers or other towerstructures (as in the depicted example), rooftops or other structures(e.g. building facades, church steeples, billboards, etc. . . . ) havingwireless communication infrastructure, mobile vehicles and vessels,and/or the like. Moreover, in existing wireless networks, it is to beappreciated that some cells 102 may overlap or completely encompass oneanother, and/or coverage gaps may exist between some cells 102, etc.,though FIG. 1 shows a deployment of substantially adjacent cells thatare deployed to provide continuous coverage over a relatively largearea.

It should be appreciated that although the cells 102 of FIG. 1 are shownhaving a particular shape (i.e., a hexagonal shape), cells of examplenetworks could have any shape depending on terrain and/or buildingconstraints. Moreover, it should also be appreciated that although theaccess points 104 of FIG. 1 are shown to be positioned substantially inthe center of the cells 102 with coverage being provided substantially360 degrees around each respective one of the access points 104, thisstructure is not required in all examples. To the contrary, accesspoints 104 could be at cell edges or at any other position within thecells 102, and the cells 102 could take any suitable shape dictated bythe radiation patterns and sector coverage deployments of the antennasand antenna arrays provided at each respective one of the access points104. It should also be appreciated that although the cells 102 aregenerally depicted to end their respective coverage areas where thecorresponding coverage area of an adjacent cell begins, there willtypically be some amount of overlap in coverage areas of adjacent cells102. Moreover, in one example embodiment, cells may have a half circleshape and may be comprised of wedge shaped coverage areas that overlapeach other to provide a continuous coverage up to a predeterminedaltitude (e.g., about 40,000 feet). In such an example, the accesspoints 104 may be positioned approximately at the center of the halfcircular shaped cells.

Example embodiments may be practiced with respect to communicationsbetween access points that are terrestrial or satellite based. Moreover,the mobile communication nodes supported could be on land, sea or in theair. In an example embodiment in which the wireless network 100 is anair-to-ground (ATG) network, the access points 104 may be enabled toestablish wireless communication links to aircraft 110 or mobilecommunication nodes disposed thereon. The aircraft 110 can be expectedto move through the network 100 in such a way as to require handoverbetween various ones of the access points 104 in order to maintaincontinuous and uninterrupted communication between the mobilecommunication node(s) on the aircraft 110 and the network devices towhich the backhaul connections couple the access points 104. Given thatthe cells 102 in an ATG network define three dimensional (3D) coverageareas that extend up to the predetermined altitude, it should thereforealso be appreciated that the borders or edges between cells 102 may varybased on altitude. Thus, the borders between cells 102 in FIG. 1 mayapply at a particular altitude. However, the borders may be different(or the same) at other altitudes. Thus, unlike a typical terrestrialnetwork, where a change in latitude and longitude coordinates wouldtypically be the driving determiner for which cell 102 the mobilecommunications nodes of the network select for communication purposes,within the network 100, a handover between cells could be necessitatedor desirable merely on the basis of altitude change for a given locationin terms of latitude and longitude coordinates.

As shown in FIG. 1, the aircraft 110 may follow a route 120 that causesthe aircraft 110 to pass through certain ones of the cells 102. As theaircraft 110 passes through each respective one of the cells 102 alongthe route 120, the mobile communication node (or nodes) of the aircraft110 may communicate with the respective 104 access points of the cells102 along the route 120. However, the communication node (or nodes) ofthe aircraft 110 may not encounter or ever communicate with a number ofthe cells 102. In particular, the aircraft 110 may not communicate withcells 102 that are located remotely from the route 120.

Meanwhile, there may also be certain areas along the route 120 at whichthe aircraft 110 may be in or next two multiple cells 102 at aparticular point in time. For example, in overlap region 130, the route120 carries the aircraft 110 near the intersection of three differentcells (e.g., a first cell 140, a second cell 142 and a third cell 144).The route 120 initially has the aircraft 110 completely within the firstcell 140. However, the route 120 then carries the aircraft 110 proximateto the second cell 142. In this example, the aircraft 110 may actuallyspend a short time proximate to edges of the first cell 140, the secondcell 142 and the third cell 144 at the same time. Then, the route 120may provide that the aircraft 110 travels along the edge between thesecond cell 142 and the third cell 144 for a relatively long period oftime.

In some networks, the mobile communication nodes on the aircraft 110 maybe configured to request handover based on signal strength changes orthe like in order to attempt to maintain continuous and uninterruptedcoverage. Alternatively, the access points 104 may communicate with eachother and the mobile communication nodes to handle handover decisionsbased on signal strength or other criteria. Meanwhile, according to someexample embodiments, load balancing, antenna beamsteering, and/orinterference mitigation (or prevention) may be accomplished by utilizinga network device that is configured to track and/or monitor positioninformation regarding the aircraft 110 (and therefore also the positionof the mobile communication nodes thereon) in order to make networkcontrol decisions.

In an ATG communications system, the end-user equipment (e.g., wired andwireless routers, mobile phones, laptop computers, on-boardentertainment systems, and/or the like) may be installed or otherwisepresent on the aircraft 110. The user equipment (UE) and any receivingand/or routing device on the aircraft 110 itself may form mobilecommunication nodes of the wireless network 100. However, as mentionedabove, the utilization of position information associated with thesemobile communication nodes may not simply involve knowledge of latitudeand longitude, relative positioning, global positioning system (GPS)coordinates, and/or the like. Instead, knowledge of 3D positioninformation including altitude and bearing may be required to give anaccurate picture of mobile communication location for use in determiningwhich access point 104 is best situated to provide optimum wirelessconnectivity for the mobile communication nodes. If the UE or theaircraft 110 is installed with a GPS device, Automatic DependentSurivellance-Broadcast (ADS-B) or other internally or externally derivedmeans of tracking location, speed, and altitude, then thislocation-specific information may be employed by the wireless system toenhance network control functions to provide load balancing, antennabeamsteering, interference mitigation, network security or recovery fromdenial of service. For example, the network may be aware of the location(which may be defined by GPS coordinates, range and bearing from areference point, or the like) of each mobile communication node of thesystem in the three-dimensional airspace, and the network may thereforefurther be capable of controlling the frequencies, channels,transmission power, or other activity of the network assets (e.g.,mobile communication nodes and/or access points 104) to improve networkefficiency and/or performance. In some cases, the network may furtherdetermine or access information indicative of the bearing and airspeedof the aircraft 110 and/or the flight plan of the aircraft 110 in orderto make predictive or anticipatory control decisions for operation ofnetwork assets. In particular, the control decisions may include theselective taking of active measures to perform noise cancellation toimprove signal to noise ratios. For example, the interference profilefor the position of the aircraft 110 (from the perspective of theaircraft 110 or the access point 104) may be used to identify specificnoise signals to be canceled for the aircraft 110 and/or the accesspoint 104.

In some example embodiments, information about the wireless network 100configuration (e.g., the locations of the access points 104 and/or thelocations or coverage areas of the cells 102 in terms of 3D space) maybe stored in memory of a network entity. The network entity, with itsknowledge of the configuration of the wireless network 100, and furtherwith knowledge of the locations of the various mobile communicationnodes, may be configured to assess the interference picture, currentlyand in the future, that the assets of the wireless network 100 areencountering or will encounter. An interference profile may then be usedto tailor the performance of one or more of the antennas to be employedfor communications between the access points 104 and the aircraft 110 tothe interference picture by canceling signals of known interferers fromthe interference profile for the area.

In some cases, the network entity may be the same or a different networkentity than that which is engaged to identify a best-serving accesspoint for handover management or to further consider the load on eachaccess point, the risk of interference, or other network performanceparameters in making decisions on how to control network assets.

Accordingly, for example, the wireless network 100 of some embodimentsmay be configured to employ assets and/or equipment to actively orpassively track mobile communication nodes (e.g., aircraft or UEs in thenetwork) in the 3D airspace. As an example, the aircraft 110 (or devicesthereon) taking off from an airport may access and synchronize with abase station near the airport. Once known to the wireless system, theaircraft 110 (or devices thereon) may periodically or continuouslytransmit position information (e.g., coordinates, altitude, directionand speed) to the serving base station. The base station may share theposition information with a centralized server or other device in thecore network. The centralized server (or other processing device) maythen track, or predict the track for, the aircraft 110 (or devicesthereon) and each other aircraft or device in the wireless network 100in order to compare the network asset location (i.e., dynamic positioninformation) against the database of access point locations of thewireless network 100. The centralized server may then be configured todetermine when a particular aircraft (or device thereon) may be movinginto or proximate to a different access point's coverage area. Thecentralized server may then provide instructions to various ones of thenetwork assets (e.g., to the aircraft 110 (or a device thereon) or tothe access point 104 (or a device thereat)) to provide interferencemitigation functions on the basis of known interferers in the regionbased on the position information. In an example embodiment, thecentralized server may be referred to as a network controller for thepurposes of explanation of an example embodiment. In such an example,all or a majority of the processing needed to inform the network assetsof at least an identity of the interfering signals (or the interferenceprofile) may be provided by the network controller. Then noisecancellation can be accomplished for the antennas of the network assetsby instances of a spectrum scrubber disposed at corresponding ones ofsuch network assets.

Some example embodiments may therefore combine knowledge of networkasset location (e.g., including fixed base station (or access point)positions (e.g., in 2D) and moving receiving station positions and/orpredictions of future positions (e.g., in 3D)) and knowledge of knowninterferers in respective locations of the network to enable intelligentinterference mitigation to scrub or remove noise from the spectrum beingused for wireless communication for either or both of the airplane (ordevices thereon) and the access points. Improved network efficiency andperformance may therefore be maintained within an ATG system (or anyother system involving mobile communication nodes), reducing the cost ofnetwork coverage and improving both handoff reliability and continuityof network connectivity for a given segment of RF spectrum. The improvedefficiency and performance may potentially enable the wireless network100 to be built with access points that are much farther apart than thetypical distance between base stations in a terrestrial network andusing crowded spectrum that may be filled with known interferingsignals. In some cases, even unlicensed band communication may beconducted over long distances in a reliable manner by employing exampleembodiments since many of the potential WiFi interferers in a givenregion may be fairly constant and can thus be accounted for by spectrumscrubbing as described herein.

FIG. 2 illustrates a functional block diagram of an ATG communicationnetwork that may employ an example embodiment. As shown in FIG. 2, afirst access point 200 and a second access point 202 may each be basestations (e.g., examples of access points 104) of an example embodimentof the wireless network 100, which in this case may be an ATG network210. The ATG network 210 may further include other access points (APs)as well, and each of the APs may be in communication with the ATGnetwork 210 via a gateway (GTW) device 220. The ATG network 210 mayfurther be in communication with a wide area network such as theInternet 230, Virtual Private Networks (VPNs) or other communicationnetworks. In some embodiments, the ATG network 210 may include orotherwise be coupled to a packet-switched core or othertelecommunications network.

In an example embodiment, the ATG network 210 may include a networkcontroller 240 that may include, for example, switching functionality.Thus, for example, the network controller 240 may be configured tohandle routing voice, video or data to and from the aircraft 110 (or tomobile communication nodes of or on the aircraft 110) and/or handleother data or communication transfers between the mobile communicationnodes of or on the aircraft 110 and the ATG network 210. In someembodiments, the network controller 240 may function to provide aconnection to landline trunks when the mobile communication nodes of oron the aircraft 110 is involved in a call. In addition, the networkcontroller 240 may be configured for controlling the forwarding ofmessages and/or data to and from the mobile communication nodes of or onthe aircraft 110, and may also control the forwarding of messages forthe access points. It should be noted that although the networkcontroller 240 is shown in the system of FIG. 2, the network controller240 is merely an exemplary network device and example embodiments arenot limited to use in a network employing the network controller 240.Moreover, although the network controller 240 is shown as a part of theATG network 210 that is ground based, it should be appreciated that thenetwork controller 240 could, in some embodiments, be provided on anaircraft to support aircraft to aircraft communications in a public orprivate mesh network environment. Furthermore, although the networkcontroller 240 is shown as being communicatively coupled to the ATGnetwork 210, it should be appreciated that the network controller 240could be instantiated as part of the ATG network 210, at the aircraft110, at any one or multiple ones of the APs, or in a separate network(e.g., accessible via the Internet 230).

The network controller 240 may be coupled to a data network, such as alocal area network (LAN), a metropolitan area network (MAN), and/or awide area network (WAN) (e.g., the Internet 230) and may be directly orindirectly coupled to the data network. In turn, devices such asprocessing elements (e.g., personal computers, laptop computers,smartphones, server computers or the like) can be coupled to the mobilecommunication nodes of or on the aircraft 110 via the Internet 230. Thenetwork controller 240 may include components and/or entities that areconfigured to obtain, learn, save, define or otherwise provide to othersystem components, one or more interference profiles 250 as describedherein.

Although not every element of every possible embodiment of the ATGnetwork 210 is shown and described herein, it should be appreciated thatthe mobile communication nodes of or on the aircraft 110 may be coupledto one or more of any of a number of different public or privatenetworks through the ATG network 210. In this regard, the network(s) canbe capable of supporting communication in accordance with any one ormore of a number of first-generation (1G), second-generation (2G),third-generation (3G), fourth-generation (4G) and/or future mobilecommunication protocols or the like. In some cases, the communicationsupported may employ communication links defined using unlicensed bandfrequencies such as 2.4 GHz or 5.8 GHz.

As shown in FIG. 2, in some cases, the aircraft 110 and/or the APs(e.g., the first AP 200 in this example) may include or host an instanceof a spectrum scrubber 400 in accordance with an example embodiment. Thespectrum scrubber 400 may be provided with or otherwise access theinterference profile 250 for an area based on the dynamic positioninformation associated with the aircraft 110. Thus, for the example ofFIG. 2, the network controller 240 may determine for a given AP (e.g.,the first AP 200) that the aircraft 110 is being served or will soon beserved by the given AP. The network controller 240 may then provide theinterference profile 250 that is generated or stored for the area of thefirst AP 200 to one or both of the spectrum scrubbers 400 of theaircraft 110 and the first AP 200. The spectrum scrubbers 400 may theninterface with the antennas of the communication equipment of theaircraft 110 and/or the first AP 200 to perform noise cancellation forany noise sources identified in the interference profile 250.

FIG. 3 illustrates one possible architecture for implementation of thenetwork controller 240 in accordance with an example embodiment. Thenetwork controller 240 may include processing circuitry 310 configuredto provide control outputs and/or information for network assets basedon processing of various input information including positioninformation of mobile communication nodes of the network. The processingcircuitry 310 may be configured to perform data processing, controlfunction execution and/or other processing and management servicesaccording to an example embodiment. In some embodiments, the processingcircuitry 310 may be embodied as a chip or chip set. In other words, theprocessing circuitry 310 may comprise one or more physical packages(e.g., chips) including materials, components and/or wires on astructural assembly (e.g., a baseboard). The structural assembly mayprovide physical strength, conservation of size, and/or limitation ofelectrical interaction for component circuitry included thereon. Theprocessing circuitry 310 may therefore, in some cases, be configured toimplement an embodiment of the present invention on a single chip or asa single “system on a chip.” As such, in some cases, a chip or chipsetmay constitute means for performing one or more operations for providingthe functionalities described herein.

In an example embodiment, the processing circuitry 310 may include oneor more instances of a processor 312 and memory 314 that may be incommunication with or otherwise control a device interface 320 and, insome cases, a user interface 330. As such, the processing circuitry 310may be embodied as a circuit chip (e.g., an integrated circuit chip)configured (e.g., with hardware, software or a combination of hardwareand software) to perform operations described herein. However, in someembodiments, the processing circuitry 310 may be embodied as a portionof an on-board computer. In some embodiments, the processing circuitry310 may communicate with various components, entities and/or sensors ofthe ATG network 210.

The user interface 330 (if implemented) may be in communication with theprocessing circuitry 310 to receive an indication of a user input at theuser interface 330 and/or to provide an audible, visual, mechanical orother output to the user. As such, the user interface 330 may include,for example, a display, one or more levers, switches, indicator lights,touchscreens, proximity devices, buttons or keys (e.g., functionbuttons), and/or other input/output mechanisms.

The device interface 320 may include one or more interface mechanismsfor enabling communication with other devices (e.g., modules, entities,sensors and/or other components/devices of the ATG network 210). In somecases, the device interface 320 may be any means such as a device orcircuitry embodied in either hardware, or a combination of hardware andsoftware that is configured to receive and/or transmit data from/tomodules, entities, sensors and/or other components/devices of the ATGnetwork 210 that are in communication with the processing circuitry 310.

The processor 312 may be embodied in a number of different ways. Forexample, the processor 312 may be embodied as various processing meanssuch as one or more of a microprocessor or other processing element, acoprocessor, a controller or various other computing or processingdevices including integrated circuits such as, for example, an ASIC(application specific integrated circuit), an FPGA (field programmablegate array), or the like. In an example embodiment, the processor 312may be configured to execute instructions stored in the memory 314 orotherwise accessible to the processor 312. As such, whether configuredby hardware or by a combination of hardware and software, the processor312 may represent an entity (e.g., physically embodied in circuitry—inthe form of processing circuitry 310) capable of performing operationsaccording to embodiments while configured accordingly. Thus, forexample, when the processor 312 is embodied as an ASIC, FPGA or thelike, the processor 312 may be specifically configured hardware forconducting the operations described herein. Alternatively, as anotherexample, when the processor 312 is embodied as an executor of softwareinstructions, the instructions may specifically configure the processor312 to perform the operations described herein.

In an example embodiment, the processor 312 (or the processing circuitry310) may be embodied as, include or otherwise control the operation ofthe network controller 240 based on inputs received by the processingcircuitry 310 responsive to receipt of position information associatedwith various relative positions of the communicating elements of thenetwork. As such, in some embodiments, the processor 312 (or theprocessing circuitry 310) may be said to cause each of the operationsdescribed in connection with the network controller 240 in relation toadjustments to be made to network configuration relative to providingservice between access points and mobile communication nodes responsiveto execution of instructions or algorithms configuring the processor 312(or processing circuitry 310) accordingly. In particular, theinstructions may include instructions for processing 3D positioninformation of the mobile communication nodes (e.g., on an aircraft)along with 2D position information of fixed transmission sites in orderto select a relevant interference profile for network assets (e.g., theaircraft or the fixed transmission site serving the aircraft). Therelevant interference profile may then be used by the spectrum scrubber400 of network assets to perform noise cancellation relative to knowninterferers to mitigate interference, increase efficiency or otherwiseimprove network performance associated with establishing a communicationlink between the mobile communication nodes and respective ones of thefixed transmission stations or access points as described herein.

In an exemplary embodiment, the memory 314 may include one or morenon-transitory memory devices such as, for example, volatile and/ornon-volatile memory that may be either fixed or removable. The memory314 may be configured to store information, data, applications,instructions or the like for enabling the processing circuitry 310 tocarry out various functions in accordance with example embodiments. Forexample, the memory 314 could be configured to buffer input data forprocessing by the processor 312. Additionally or alternatively, thememory 314 could be configured to store instructions for execution bythe processor 312. As yet another alternative, the memory 314 mayinclude one or more databases that may store a variety of data setsresponsive to input sensors and components. Among the contents of thememory 314, applications and/or instructions may be stored for executionby the processor 312 in order to carry out the functionality associatedwith each respective application/instruction. In some cases, theapplications may include instructions for providing inputs to controloperation of the network controller 240 as described herein.

In an example embodiment, the memory 314 may store fixed positioninformation 350 indicative of a fixed geographic location of accesspoints of the ATG network 210. In some embodiments, fixed positioninformation 350 may be indicative of the fixed geographic location ofmultiple ones (or even all) of the access points of the ATG network 210.The fixed position information 350 may be read out of memory andprovided to (and therefore also received at) the processing circuitry310 for processing in accordance with an example embodiment.

In an example embodiment, the processing circuitry 310 may be configuredto receive dynamic position information 360 indicative of a threedimensional position and/or altitude and relative bearing and range ofat least one mobile communication node (which should be appreciated tobe capable of transmission and reception of signaling in connection withtwo way communication). In an example embodiment, the dynamic positioninformation 360 may include latitude and longitude coordinates andaltitude to provide a position in 3D space. In some cases, the dynamicposition information 360 may further include heading and speed so thatcalculations can be made to determine, based on current location in 3Dspace, and the heading and speed (and perhaps also rate of change ofaltitude and heading), a future location of the aircraft 110 at somefuture time. In some cases, flight plan information may also be used forpredictive purposes to either prepare assets for future network controlactions that are likely to be needed, or to provide planning for networkasset management purposes.

The dynamic position information 360 may be determined by any suitablemethod, or using any suitable devices. For example, the dynamic positioninformation 360 may be determined using global positioning system (GPS)information onboard the aircraft 110, using data from AutomaticDependent Surveillance-Broadcast (ADS-B) or other such systems, based ontriangulation of aircraft position based on a direction from which aplurality of signals arrive at the aircraft 110 from respective ones ofthe access points, using aircraft altimeter information, using radarinformation, and/or the like, either alone or in combination with eachother. The mobile communication node may be a passenger device onboardthe aircraft 110, or may be a wireless communication device of theaircraft 110 itself. The wireless communication device of the aircraft110 may transfer information to and from passenger devices (with orwithout intermediate storage), or may transfer information to and fromother aircraft communications equipment (with or without intermediatestorage).

In an example embodiment, the processing circuitry 310 may be configuredto determine a relative position of the aircraft 110 (or multipleaircraft) relative to one or more of the access points (e.g., the firstaccess point 200, second access point 202 or other APs) based on thefixed position information 350 and the dynamic position information 360.In other words, the processing circuitry 310 may be configured toutilize information indicative of the locations of two devices ornetwork assets and determine where the network assets are relative toone another from the perspective of either one of the network assets (orboth). Of note, while the “relative position” could take the form of arange and bearing from a particular reference point (e.g., an accesspoint), the relative position need not be that specific in all cases.Instead, the relative position could be a determination of the nearestaccess point to the aircraft 110 based on the fixed position information350 and the dynamic position information 360. Additionally oralternatively, the relative position could be a determination of theaccess points that are within communication range (i.e., which accesspoints are relatively close to the aircraft 110). In some embodiments,such determination may further include ranking the access points basedon current distance (or signal strength) and/or based on estimates offuture distance (or signal strength) based on a predicted futureposition of the aircraft 110 (and nodes thereon).

Accordingly, in some embodiments, tracking algorithms may be employed totrack dynamic position changes and/or calculate future positions basedon current location and rate and direction of movement. Thus, therelative position may, in some cases, be a predicted future position asmentioned above. The network controller 240 may therefore not only beable to determine the best one or more access points for the nodes ofthe aircraft 110 to connect to at any given point along the route 120,but the network controller 240 may also determine the access points thatare likely to be the best access points for connection in the future fora predetermined period of time or even for the entire route. Thus, forexample, the network controller 240 may be configured to determine aroute communication plan that may define the access points to contactalong the route 120 and corresponding times or locations for which therespective access points are the best access points. In some cases, anFAA flight plan may be used to determine the route communication plan.Alternatively or additionally, the network controller 240 may estimatethe route communication plan on the basis of information entered by theflight crew and/or historical information. Accordingly, for example, theroute communication plan may provide a list of access point identifiersfor which the nodes of the aircraft 110 should listen as each respectivecell is approached so that handovers can be handled more easily andefficiently. Thus, the nodes can avoid or mitigate interference impactsby focusing in on a particular frequency or channel that is known inadvance by looking for a particular access point identifier at aparticular time when it is known that the access point identifier shouldbe within or close to within range.

In an example embodiment, the memory 314 may additionally store aninterferer library 370. The interferer library 370 may be a library orcollection of noise sources. The library may be built based on theclassification, identification or recording of noise sources that areexperienced in a particular area with at least a threshold amount ofregularity. As such, for example, if the first AP 200 is operating inthe particular area using unlicensed band frequencies, the first AP 200may be proximate to (or within communication range of) one or moreunlicensed band transmitters (e.g., WiFi routers) that are frequentlytransmitting interfering (or potentially interfering) signals in thearea. When the antenna of the first AP 200 receives potentiallyinterfering signals, such signals may be analyzed by the processingcircuitry 310 for classification or recognition as a local interferer.If a potentially interfering signal is noted or detected a thresholdnumber of times (generally or within a given period), the potentiallyinterfering signal may be recorded or otherwise classified in theinterferer library 370. Thus, the interferer library 370 may bedynamically updateable based on sensing the current environment to addnew potentially interfering signals to the interferer library 370.Similarly, if a previously known potentially interfering signal is notexperienced or sensed in a given area for a predetermined period oftime, the previously known potentially interfering signal may be deletedfrom the interferer library 370.

In some embodiments, the interferer library 370 may be descriptive of orotherwise record interference signals in association with theirrespective locations. In some cases, the respective locations may be acell identifier, geographic coordinates (e.g., GPS coordinates,latitude/longitude, etc.), a relative position or direction from a fixedtransmission site, and/or the like. As such, in some cases, theinterferer library 370 may include information descriptive ofinterference signals for a given location that can be the same for boththe aircraft 110 and the serving AP (e.g., the first AP 200) when theaircraft 110 is being served by a particular AP (e.g., the first AP200). In such an example, the interference profile 250 provided to boththe aircraft 110 and the first AP 200 may be the same when the aircraft110 is served by the first AP 200. However, because finer positioninformation, including a directional component, is also available, theinterference profile 250 could be different for the aircraft 110 and thefirst AP 200 when the aircraft 110 is being served by the first AP 200.For example, if the aircraft 110 is transiting across a sector fromNorth to West (relative to the first AP 200), the first AP 200 may notexpect to receive any interference from a known interferer that islocated to the Southeast of the first AP 200 when forming directionalbeams toward the aircraft 110 to communicate with the aircraft 110.However, it may be possible for the aircraft 110, when formingdirectional beams toward the first AP 200, to receive interference fromthe known interferer. Thus, for example, the interference profile 250provided to the aircraft 110 may identify the known interferer, but theinterference profile 250 provided to the first AP 200 may not includethe known interferer.

In some embodiments, the network controller 240 may determine, inreal-time or in advance, the cells through or proximate to which theaircraft 110 (or multiple aircraft) passes. Cells through or proximateto which each aircraft route passes may be selected cells. For eachselected cell, the network controller 240 may reference the interfererlibrary 370 to select applicable interferers that are likely (e.g.,above a threshold amount of likelihood) to interfere with the aircraft110 and/or fixed transmission sites in the selected cells. Likelyinterferers may then be selected for addition to the interferenceprofile 250 to be provided to the aircraft 110 and/or its serving fixedtransmission site.

In an example embodiment, the interference profile 250 may betransmitted to the network assets for use by the spectrum scrubber 400at each respective network asset. However, it should be appreciated thatthe provision of the interference profile 250 need not be necessarilycommunicated remotely in all cases. In this regard, the networkcontroller 240 may be a distributed asset, or may be embodied at theaircraft 110 or the fixed transmission sites themselves. Thus, in someexamples, the interference profile 250 may actually be generated locallyand the network controller 240 and spectrum scrubber 400 can becollocated or even the same device. However, in other examples, thenetwork controller 240 may be a single device within the ATG network210, or multiple regional network controllers may serve specificgeographic regions and corresponding APs provided within the region.

Regardless of whether the provision of the interference profile 250 isconducted in real time, or includes future planning, the networkcontroller 240 may be configured to provide the interference profile 250to the spectrum scrubber 400 to enable the spectrum scrubber 400 to takeactive measures to mitigate interference by employing noise cancellationtechniques.

FIG. 4 illustrates a block diagram of the structure of the spectrumscrubber 400 in accordance with an example embodiment. As shown in FIG.4, the spectrum scrubber 400 may include processing circuitry 410 thatincludes a processor 412 and memory 414. The spectrum scrubber 400 mayalso include a device interface 420 (and in some cases also a userinterface 430). The processing circuitry 410, processor 412, memory 414,device interface 420 and user interface 430 (if employed) may be similarin functional capability (and some cases also in form) to thecorresponding processing circuitry 310, processor 312, memory 314,device interface 320 and user interface 330 except perhaps fordifferences in scale and configuration. Thus, details regarding thestructure and capability of the processing circuitry 410, processor 412,memory 414, device interface 420 and user interface 430 will not berepeated.

In an example embodiment, the spectrum scrubber 400 may further includea noise canceller 450 that subtracts selected noise signals orinterference signals out of a received signal received from an antenna460 of the corresponding network asset (e.g., the aircraft 110, thefirst AP 200, the second AP 202, other APs, or individual UEs configuredwith an instance of the spectrum scrubber 400). Thus, for example, theinterference profile 250 for the area in which the network asset islocated may be provided to the spectrum scrubber 400. The interferenceprofile 250 may identify one or more interference signals and one ormore interference signals (e.g., interference signal 252) may beprovided to the noise canceller 450 based on the interference profile250. Signal plus noise 470 associated with a received signal from theantenna 460 may then be provided to the noise canceller 450, which maysubtract the interference signal 252 from the signal plus noise 470 togenerate a scrubbed signal 480 that can then be passed along to thesignal processor 490 of the corresponding network asset. The signalprocessor 490 may then perform signal processing techniques to decodethe received signal and extract the signal and any informationtherefrom.

The noise canceller 450 may be any means such as a device or circuitryembodied in either hardware, or a combination of hardware and softwarethat is configured to subtract a known local interferer signal from areceived signal to provide a cleaner signal (e.g., the scrubbed signal480) that has at least some of the known noise for the current locationof the network asset employing the noise canceller 450 removed. In someexamples, the noise canceller 450 may be provided as hardware used forcontrol of antenna components or signal processor or processing chaincomponents. For example, in some cases, the noise canceller 450 may beprovided via a tunable filter. Thus, for example, a tunable notch filtermay be provided and the filter may be tuned to exclude the interferencesignal 252 (or signals). In an example embodiment, the tunable notchfilter may define a frequency or range of frequencies at whichinterfering signals are removed. However, time domain notching may alsobe performed and, in some cases, time domain notching, frequency domainnotching, or combinations of time and frequency domain notching may beperformed for noise cancellation by the noise canceller 450. In someexamples, the noise canceller 450 may be embodied via steering a null ofthe antenna 460 toward a known relative location of the noise signal(i.e., the interference signal 252). For example, null steering may beperformed by steering a null toward the direction of arrival of thenoise signal in connection with Multiple Signal Classification (i.e.,the MUSIC algorithm), Estimation of Signal Parameters via RotationalInvariance Technique (ESPRIT) and/or the like. Spatial smoothingtechniques may be employed to reduce the complexity of direction ofarrival determinations in some cases.

In some alternatives, the noise canceller 450 may employ software orfirmware to numerically remove the interference signal 252 (as shown inthe example of FIG. 4). The numerical removal of the interference signal252 can be performed as part of the signal processing chain (e.g., atthe back end) or proximate to the antenna (e.g., a the front end). MonteCarlo sampling, Bayesian filtering, Newton's method or other numericalanalysis techniques may be employed in relation to the numerical removalof the interference signal 252. Other techniques for noise cancellationare also possible. Moreover, in some cases, the noise canceller 450 mayoperate as part of an algorithm for removal of noise to find a best linkbudget in a particular scenario or situation.

By employing the noise canceller 450, the spectrum scrubber 400 mayprovide a dynamic capability for targeted “spectrum cleansing” toeliminate known interference signals so that signal processing may bemore effective in a crowded segment of spectrum. However, regardless ofwhether crowded spectrum is employed, the elimination of knowninterferers, and the dynamic provision of the identities of such knowninterferers to assets moving between areas, can improve the efficiencyand effectiveness of wireless communications. As such, the networkassets become situationally aware assets that can take active steps toremove WiFi, Zigbee, or other potentially known interferer signals formobile communication devices.

Similar to the example mentioned above, when the spectrum scrubber 400receives a potentially interfering signal, such signal may be analyzedby the processing circuitry 410 for classification or recognition as alocal interferer. Alternatively or additionally, information descriptiveof the signal may be communicated to the network controller 240 for suchanalysis. If a potentially interfering signal is noted or detected athreshold number of times (generally or within a given period), thepotentially interfering signal may be recorded or otherwise classifiedin the interferer library 370 at the network controller 240, or at alocal instance of the interferer library, which could be maintained atthe spectrum scrubber 400. In any case, as mentioned above, theinterferer library may be dynamically updateable based on sensing thecurrent environment to add new potentially interfering signals to theinterferer library. When detected at the spectrum scrubber 400, detectsthe signal, such detection could be made via the antenna 460 in a modethat does not employ the noise canceller 450. However, in someembodiments, a separate antenna (e.g., sniffer antenna 495) may beprovided to detect and/or facilitate classification of potentiallyinterfering signals. The sniffer antenna 495 may also be configured todetect potential interferers on an aircraft, for example. Thus, thesignals generated by devices of users on the aircraft, or othertransmitters on the aircraft, may be detected and classified using thesniffer antenna 495. Thus, for example, internal access points, WiFihotspots or other devices, Bluetooth devices, etc., may be detected andclassified as interferers for cancellation. Thereafter, theidentified/classified signals may be used to generate the interferencesignal 252 (in parallel with or independent of the interference profile250) for cancellation by the noise canceller 450 as otherwise describedherein.

As such, the system of FIG. 2 may provide an environment in which thenetwork controller 240 of FIG. 3 and the spectrum scrubber 400 of FIG. 4may provide a mechanism via which a number of useful methods may bepracticed. FIG. 5 illustrates a block diagram of one method that may beassociated with the system of FIG. 2 and the network controller 240 ofFIG. 3 and the spectrum scrubber 400 of FIG. 4. From a technicalperspective, the network controller 240 and/or the spectrum scrubber 400described above may be used to support some or all of the operationsdescribed in FIG. 5. As such, the platform described in FIG. 2 may beused to facilitate the implementation of several computer program and/ornetwork communication based interactions. As an example, FIG. 5 is aflowchart of a method and program product according to an exampleembodiment. It will be understood that each block of the flowchart, andcombinations of blocks in the flowchart, may be implemented by variousmeans, such as hardware, firmware, processor, circuitry and/or otherdevice associated with execution of software including one or morecomputer program instructions. For example, one or more of theprocedures described above may be embodied by computer programinstructions. In this regard, the computer program instructions whichembody the procedures described above may be stored by a memory device(e.g., of the network controller 240 or spectrum scrubber 400) andexecuted by a processor in the device. As will be appreciated, any suchcomputer program instructions may be loaded onto a computer or otherprogrammable apparatus (e.g., hardware) to produce a machine, such thatthe instructions which execute on the computer or other programmableapparatus create means for implementing the functions specified in theflowchart block(s). These computer program instructions may also bestored in a computer-readable memory that may direct a computer or otherprogrammable apparatus to function in a particular manner, such that theinstructions stored in the computer-readable memory produce an articleof manufacture which implements the functions specified in the flowchartblock(s). The computer program instructions may also be loaded onto acomputer or other programmable apparatus to cause a series of operationsto be performed on the computer or other programmable apparatus toproduce a computer-implemented process such that the instructions whichexecute on the computer or other programmable apparatus implement thefunctions specified in the flowchart block(s).

Accordingly, blocks of the flowchart support combinations of means forperforming the specified functions and combinations of operations forperforming the specified functions. It will also be understood that oneor more blocks of the flowchart, and combinations of blocks in theflowchart, can be implemented by special purpose hardware-based computersystems which perform the specified functions, or combinations ofspecial purpose hardware and computer instructions.

In this regard, a method according to one example embodiment, as shownin FIG. 5, may include receiving information indicative of a localinterferer at operation 500. The local interferer may be identifiedbased on dynamic position information indicative of a position of atleast one mobile communication node. Noise cancellation may then beperformed relative to a received signal by removing an interferencesignal associated with the local interferer to generate a scrubbedsignal at operation 510. Thereafter, at operation 520, the scrubbedsignal may be provided for additional signal processing.

Defining the interference profile may be accomplished based on selectinglocal interferers from an interferer library based on the dynamicposition information. As such, the relative position between the mobilecommunication node and the fixed or serving site may allow someinterferers in the interferer library to be excluded from inclusion inthe interference profile based on having a low likelihood of interferinggiven the relative position. Thereafter, performance of noisecancellation may be accomplished based on the interference profile atoperation 520. The noise cancellation may include subtracting one ormore interference signals from received signals to define a scrubbedsignal. At operation 530, signal processing may be performed (e.g., onthe scrubbed signal).

In some embodiments, the method may include additional, optionaloperations, and/or the operations described above may be modified oraugmented. Some examples of modifications, optional operations andaugmentations are described below. It should be appreciated that themodifications, optional operations and augmentations may each be addedalone, or they may be added cumulatively in any desirable combination.In an example embodiment, the dynamic position information may include athree dimensional position of an aircraft. In some cases, the localinterferer may be identified in an interference profile indicative ofone or more interference signals associated with the three dimensionalposition of the aircraft. In an example embodiment, the interferenceprofile may be received at the aircraft from a network entity, and theinterference profile may be received substantially in real time based onthe three dimensional position of the aircraft, or for a projectedfuture position of the aircraft. Alternatively or additionally, theinterference profile may be received, from a network entity, at a fixedtransmission site communicating with the aircraft, and the interferenceprofile may be received substantially in real time based on the threedimensional position of the aircraft, or for a projected future positionof the aircraft. In some cases, the interference profile may be providedto both the aircraft and a fixed transmission site communicating withthe aircraft. However, in some cases, the interference profile may beprovided to one of the aircraft or a fixed transmission sitecommunicating with the aircraft, and a different interference profilemay be provided to the other of the aircraft or a fixed transmissionsite communicating with the aircraft. In an example embodiment, theinterference profile may include selected interferers from an interfererlibrary including a plurality of known interferers associated withrespective different locations. The selected interferers may be selectedbased on the dynamic position information. In such an example, theinterferer library may be dynamically updateable to include additionalinterference signals detected a threshold number of times or detectedthe threshold number of times within a given period. Alternatively oradditionally, the interferer library may be dynamically updateable todelete interference signals not detected for at least a given period. Insome embodiments, performing the noise cancellation may includenumerically removing the interference signal from the received signal,steering a null toward a location of the interference signal and/ortuning a notch filter to filter out the interference signal. In thecontext of some embodiments, the at least one mobile communication nodemay be provided at a vehicle, watercraft, aircraft or satellite.

Many modifications and other embodiments of the inventions set forthherein will come to mind to one skilled in the art to which theseinventions pertain having the benefit of the teachings presented in theforegoing descriptions and the associated drawings. Therefore, it is tobe understood that the inventions are not to be limited to the specificembodiments disclosed and that modifications and other embodiments areintended to be included within the scope of the appended claims.Moreover, although the foregoing descriptions and the associateddrawings describe exemplary embodiments in the context of certainexemplary combinations of elements and/or functions, it should beappreciated that different combinations of elements and/or functions maybe provided by alternative embodiments without departing from the scopeof the appended claims. In this regard, for example, differentcombinations of elements and/or functions than those explicitlydescribed above are also contemplated as may be set forth in some of theappended claims. In cases where advantages, benefits or solutions toproblems are described herein, it should be appreciated that suchadvantages, benefits and/or solutions may be applicable to some exampleembodiments, but not necessarily all example embodiments. Thus, anyadvantages, benefits or solutions described herein should not be thoughtof as being critical, required or essential to all embodiments or tothat which is claimed herein. Although specific terms are employedherein, they are used in a generic and descriptive sense only and notfor purposes of limitation.

1. An apparatus comprising processing circuitry configured to: receiveinformation indicative of a local interferer, the local interferer beingidentified based on dynamic position information indicative of aposition of an aircraft; perform noise cancellation relative to areceived signal by removing an interference signal associated with thelocal interferer to generate a scrubbed signal; and provide the scrubbedsignal for additional signal processing, wherein the local interferer isidentified in an interference profile indicative of one or moreinterference signals associated with the position of the aircraft,wherein the interference profile includes selected interferers from aninterferer library including a plurality of known interferers associatedwith respective different locations, and wherein the interferer libraryis dynamically updateable to include additional interference signalsdetected a threshold number of times or detected the threshold number oftimes within a given period, wherein the threshold number of times is aninteger value greater than one.
 2. The apparatus of claim 1, wherein thedynamic position information comprises a three dimensional position ofthe aircraft.
 3. (canceled)
 4. The apparatus of claim 2, wherein theinterference profile is received at the aircraft from a network entity,and wherein the interference profile is received substantially in realtime based on the three dimensional position of the aircraft.
 5. Theapparatus of claim 2, wherein the interference profile is received, froma network entity, at a fixed transmission site communicating with theaircraft, and wherein the interference profile is received substantiallyin real time based on the three dimensional position of the aircraft. 6.The apparatus of claim 1, wherein the interference profile is receivedat the aircraft from a network entity, and wherein the interferenceprofile is provided for a projected future position of the aircraft. 7.The apparatus of claim 1, wherein the interference profile is received,from a network entity, at a fixed transmission site communicating withthe aircraft, and wherein the interference profile is provided for aprojected future position of the aircraft.
 8. The apparatus of claim 1,wherein the interference profile is provided to both the aircraft and afixed transmission site communicating with the aircraft.
 9. Theapparatus of claim 1, wherein the interference profile is provided toone of the aircraft or a fixed transmission site communicating with theaircraft, and a different interference profile is provided to the otherof the aircraft or a fixed transmission site communicating with theaircraft.
 10. The apparatus of claim 2, wherein the selected interferersare selected based on the dynamic position information.
 11. (canceled)12. The apparatus of claim 10, wherein the interferer library isdynamically updateable to delete interference signals not detected forat least a given period.
 13. The apparatus of claim 1, whereinperforming the noise cancellation comprises numerically removing theinterference signal from the received signal.
 14. The apparatus of claim1, wherein performing the noise cancellation comprises steering a nulltoward a location of the interference signal.
 15. The apparatus of claim1, wherein performing the noise cancellation comprises tuning a notchfilter to filter out the interference signal.
 16. (canceled)
 17. Amethod of enhancing wireless communication performance, the methodcomprising: receiving information indicative of a local interferer, thelocal interferer being identified based on dynamic position informationindicative of a position of an aircraft; performing noise cancellationrelative to a received signal by removing an interference signalassociated with the local interferer to generate a scrubbed signal; andproviding the scrubbed signal for additional signal processing, whereinthe local interferer is identified in an interference profile indicativeof one or more interference signals associated with the position of theaircraft, wherein the interference profile includes selected interferersfrom an interferer library including a plurality of known interferersassociated with respective different locations, and wherein theinterferer library is dynamically updateable to include additionalinterference signals detected a threshold number of times or detectedthe threshold number of times within a given period, wherein thethreshold number of times is an integer value greater than one.
 18. Themethod of claim 17, wherein performing the noise cancellation comprisesnumerically removing the interference signal from the received signal.19. The method of claim 17, wherein performing the noise cancellationcomprises steering a null toward a location of the interference signal.20. The method of claim 17, wherein performing the noise cancellationcomprises tuning a notch filter to filter out the interference signal.21. The apparatus of claim 1, wherein receiving information indicativeof the local interferer comprises receiving the information in advanceof the aircraft being in a cell in which the local interferer islocated, and wherein performing noise cancellation relative to thereceived signal comprises employing a noise cancellation techniqueselected in advance of the aircraft being in the cell in which the localinterference is located.
 22. The method of claim 17, wherein receivinginformation indicative of the local interferer comprises receiving theinformation in advance of the aircraft being in a cell in which thelocal interferer is located, and wherein performing noise cancellationrelative to the received signal comprises employing a noise cancellationtechnique selected in advance of the aircraft being in the cell in whichthe local interference is located.